Process for the modification of aromatic polymers via Friedel-Crafts reactions to produce novel polymers and the use thereof

ABSTRACT

A process for the addition of pendant groups to polyarylenes comprises the steps of charging a reaction vessel with a solution of a polyarylene and a Friedel-Crafts catalysts; said polyarylene having the formula ##STR1## adding to the reaction vessel a pendant forming group G, wherein G is selected from the group consisting of sulfonyl halides, sulfonamide halides, alkylhalides, acylhalides and phosphorus acid halides; heating the contents of the reaction vessel to form a substituted polyarylene having the formula ##STR2## and thereafter recovering the substituted polyarylene. The substituted polyarylenes are novel and have utility as a semipermeable membrane and a process for the separation of gases therewith is also provided.

This application is a division of application Ser. No. 657,138, filedOct. 3, 1984, now U.S. Pat. No. 4,596,860.

TECHNICAL FIELD

This invention relates to the synthesis of aromatic polymers containingpendant aromatic sulfone, sulfonamide, alkyl, acyl or phosphorus groups.Semipermeable membranes can be prepared from these polymers and used toeffect gas and liquid separations. These membranes have improvedpermselectivity over polyarylethers and polysulfones.

BACKGROUND ART

The art is replete with teachings describing various semipermeablemembranes, their preparation and use. U.S. Pat. No. 3,350,844 teachesthe enrichment of gases by permeation through a thin permeable film ormembrane prepared from a polyarylene oxide film. U.S. Pat. No. 3,780,496teaches the use of sulfonated polyxylylene oxide membranes to separatehelium, hydrogen and oxygen from gas mixtures.

While the membranes of the above teachings and others all display somelevel of utility, there exists a continuing search for new membranes andnew applications for both new and known membranes. One application wherethe use of membrane technology may prove beneficial is in the separationof gaseous carbon dioxide-methane mixtures into enriched fractions oftheir constituent parts. Natural gas is generally found in combinationwith carbon dioxide. Removal of the carbon dioxide from the natural gasis desirable because it results in both a product (purified natural gas)of greater commercial worth and it provides purified carbon dioxideuseful for other applications, such as enhanced oil recovery.Conventional separation processes generally employ cryogenic methodswhich are relatively energy intensive.

A semipermeable membrane comprising polyarylenes containing alkyl andaryl sulfone radicals and the use thereof is set forth in a copendingapplication, U.S. Ser. No. 570,976, now U.S. Pat. No. 4,521,224,commonly owned by the Assignee of record herein. Unlike the polymerforming the membranes of that invention, the present inventiondiscloses, in addition, polymers containing other groups such as alkyl,aryls and ring halogens.

DISCLOSURE OF THE INVENTION

In general, the process of the present invention comprises the steps ofcharging a reaction vessel with a solution of a polyarylene and aFriedel-Crafts catalyst, said polyarylene having the formula ##STR3##where each R is independently a C₁ to C₈ aliphatic or a C₅ to C₇cycloaliphatic radical or an aryl radical having the formula ##STR4##where each R₁ is independently a C₁ to C₈ aliphatic radical and p is aninteger of 0 to 4, each radical being free of a tertiary alpha-carbonatom; A is hydrogen, halogen, an aliphatic or an aryl radical; Y is adivalent oxygen or sulfur atom or a carbonate group and n is an integerof from about 75 to about 10,000; adding to the reaction vessel apendant forming group G, wherein G is selected from the group consistingof sulfonyl halides having the formula ##STR5## where X is a halogen andR₂ is a C₁ to C₂₀ aliphatic, an aryl radical of the formula ##STR6## ora naphtyl radical;

a sulfonamide halide having the formula ##STR7## where R₂ can be thesame or different; alkylhalides having the formula

    R.sub.3 --X                                                (V)

where X is a halogen and R₃ is a C₁ to C₂₀ aliphatic radical;

acylhalides having the formula ##STR8## where X is ahalogen and R₄ is aC₁ to C₂₀ aliphatic or an aryl radical of the formula ##STR9## and,

phosphorus acid halides having the formula

    X.sub.q --P--(R.sub.5).sub.3 -q                            (VII)

where X is a halogen; R₅ is R₄ and/or O-R₄ and q is an integer of from 1to 3;

heating the contents of said reaction vessel to form a substitutedpolyarylene having the formula ##STR10## where G is present in at leastfive percent of the polyarylene units and R, A, Y, G and n are asdescribed and, thereafter recovering the substituted polyarylene.

Novel substituted polyarylene polymers having the formula ##STR11##result from practice of the foregoing process. In this formula, each Ris indpendently a C₁ to C₈ aliphatic or a C₅ to C₇ cycloaliphaticradical, an aryl radical having the formula ##STR12## where each R₁ isindependently a C₁ to C₈ aliphatic radical and p is an integer of 0 to4, each radical being free of a tertiary alpha-carbon atom; A ishydrogen, halogen, an aliphatic or an aryl radical; Y is a divalentoxygen or sulfur atom or a carbonate group; n is an integer of fromabout 75 to about 10,000 and G is present in at least five percent ofthe polyarylene unit.

The pendant groups G are selected from the group consisting of sulfonylshaving the formula ##STR13## where R_(2a) is a C₁ to C₂₀ aliphatic or anapthyl radical; sulfonamides having the formula ##STR14## where R₂ canbe the same or different; alkyls having the formula

    R.sub.3 --                                                 (Va)

where R₃ is a C₁ to C₂₀ aliphatic radical;

acyls having the formula ##STR15## where R₄ is a C₁ to C₂₀ aliphatic oran aryl radical of the formula ##STR16## and,

phsophorus groups having the formula

    --P--(R.sub.5).sub.3-q                                     (VIIa)

where R₅ is R₄ and/or O-R₄ and q is an integer of from 1 to 3.

The foregoing substituted polymers having utility as semipermeablemembranes and the present invention also provides a process for theseparation of gases from a mixture containing at least two gases intotwo fractions, one fraction being enriched with at least one of thegases and the other fraction be depleted in the same. The process ispracticed by contacting the gaseous mixture with the novel semipermeablemembrane in such a manner that a portion of the gaseous mixtureselectively passes through the membrane resulting in the enrichedfraction being on one side of the membrane and the depleted fractionbeing on the other side of the membrane.

PREFERRED EMBODIMENT FOR CARRYING OUT THE INVENTION

The process for the addition of pendant groups G to aromatic polymers isaccomplished in a relatively simple one step reaction as follows:##STR17##

As noted above, Y can be divalent oxygen, --O--, divalent sulfur, --S--,or a carbonate group ##STR18## The definition of Y can vary from aryleneunit to arylene unit and thus a polymer of formula I can contain allthree linkages although preferably the X linkage has the same definitionthroughout the polymer, i.e., all carbonate, all oxygen or all sulfur.Divalent oxygen is the preferred definition of Y.

Typical groups represented by A in formula I besides hydrogen includehalogens, i.e., F, Cl, Br and I, the apliphatics described inconjunction with R and aryl radicals such as phenyl, tolyl, xylenyl,phenethyl and the like.

Typical aliphatic groups represented by R in formula I and the foregoingequation include methyl, ethyl, propyl, hexyl, cyclohexyl, cyclohexenyland the like. Where R is an aryl, as described in formula II,nonpolymeric aryl radicals such as phenyl, tolyl, xylenyl, phenethyl andthe like are contemplated. Thus, suitable compounds can be unsubstitutedaryl, where p =0, or alkylaryl or arylalkyl radicals. If desired, R cancontain inert substituents, i.e., substituents that are nonreactive withthe components of the permeant under separation conditions, althoughpreferably R is free of any such substituents. R is preferably a C₁ toC₄ alkyl radical and most preferably a methyl radical.

R₁ in the definition of formula II shares the C₁ to C₈ aliphaticsdiscussed in conjunction with R hereinabove. R₂ in the definition offormula III can be any linear or branched hydrocarbon having from one toabout 20 carbon atoms including saturated compounds such as methyl,ethyl, propyl, butyl, t-butyl, octyl, hexadecyl and the like, as well asunsaturated, e.g., alkenes, alkynes and the like.

R₂ can also be an aryl radical of the formula ##STR19## as notedhereinabove where each R₁ is independently a C₁ to C₈ aliphatic radical,and p is an integer of 0 to 4. If p is a positive integer (greater than0), preferably it is 1 or 2 and then R₁ is preferably a C₁ to C₃ alkylradical.

R₂ can thus also be any nonpolymeric aryl radical, such as phenyl,tolyl, xylenyl and phenethyl. By nonpolymeric is meant that the arylradical is not part of a polymer chain, i.e., the aryl radical of anarylene unit of another polymer strand of formula I or in other words,the sulfone group for instance, O═S═O, does not link two independentpolymer strands. However, the aryl radical here includes multi-ringcompounds such as biphenyl, diphenyloxide, etc. As noted, R₂ can also benaphthyl. Preferred aryl radicals are phenyl, tolyl, xylenyl andphenethyl.

R₃ in the definition of formula V shares the C₁ to C₂₀ aliphaticsdiscussed in conjunction with R₂ hereinabove. Similarly, R₄ in thedefinition of formula VI shares both the C₁ to C₂₀ aliphatics as well asthe aryl radicals of formula II, discussed in conjuntion with R₂hereinabove. Suitable acylhalides include, for instance, propionylhalide, butyryl chloride, lauroyl chloride, myristoyl chloride,palmitoyl chloride, phenylacetyl chloride, toluoyl chloride and thelike.

Suitable sulfonamide halides include compounds such as dimethylsulfamoylchloride. Suitable phosphorus acid halides include phosphorustrichloride, ethyl chlorophosphite, diphenyl chlorophosphite and thelike.

The number of pendant groups G introduced by the synthesis of thepresent invention is at least about five percent, or 0.05 mole, that is,one out of 20 of the polyarylene units will contain a G group. As anupper limit, 200 percent, or 2.0 mole, is possible, that is, everypolyarylene unit will contain two groups G. Preferably, 25 to 100percent (0.25 to 1.0 mole) will be present, or from one group G per fourpolyarylene units to one group G per polyarylene unit.

Thus, the foregoing process of the present invention allows for thesulfonylation, sulfamylation, alkylation, acylation or phosphorylationof polyarylenes particularly polyarylene ethers, where Y is oxygen.Polyphenylene oxide (PPO) is a preferred material where both R groupsare methyl and the A group is hydrogen. The weight average molecularweight of this material is typically at least about 20,000 andpreferably at least about 50,000. The maximum weight average molecularweight is limited only by practical considerations, particularly thefilm-forming ability of the polymer, but typically it does exceed about1,000,000 weight average molecular weight. These polymers and theirpreparation are defined at length in the above-referenced U.S. Pat. No.3,350,844, the subject matter of which is incorporated herein byreference.

The foregoing polymer can contain another organic group or ring.Halogenation can be provided in a conventional modification and as suchthe technique by which this is achieved does not constitute a novelaspect of the present invention. Similarly, the addition of otherorganic groups is not a novel aspect of the process inasmuch as they canbe provided either by monomer selection or by employing modificationreactions.

In order to prepare a polymer having a repeating structural unit offormula I, a Friedel-Crafts synthesis is employed. The reaction takesplace by contacting a solution of polyphenylene oxide, for instance,with sulfonyl halides, sulfamoyl halides, alkyl halides, acyl halides orphosphorus acid halides as desired, e.g., iodides, bromides, chlorides,fluorides in the presence of a Lewis acid (AlCl₃, SnCl₄, FeCl₃ and thelike). Halogenated solvents or polar solvents, particularly nitrobenzeneare employed for the reaction. Typical reaction temperatures rangebetween 0° and 100° C.; typical reaction times are from a few hours,e.g., about four to 16 hours. Reaction mixtures are usually purged withnitrogen to aid in the removal of hydrogen halide by-products.

The process of the present invention provides for the novel synthesis ofvarious substituted polyarylene polymers as described hereinabove. Themajority of these polymers are believed to be novel, the sole exceptionbeing those polymers containing the aryl sulfonyl group G where the arylhas the formula ##STR20## as set forth hereinabove. The synthesis ofsuch polymers has been set forth in U.S. Pat. No. 4,427,419, owned bythe Assignee of record and was performed by contacting PPO withchlorosulfonic acid and then an aromatic compound such as benzene ortoluene. That process is not a Friedel-Crafts technique nor is it usefulfor synthesizing sulfones containing naphthyl radicals. For naphthyl aswell as alkyl moeities, the synthesis process of the present inventionmust be employed and, therefore, substituted polymers containing thesegroups are believed to be novel.

Semipermeable membranes comprising the novel aromatic polymersynthesized herein can be manufactured by any conventional method. Inone embodiment, the polymer is dissolved in a suitable solvent to formabout a five to about a 20, preferably a seven to about a 15, weightpercent solution. Generally any polar solvent can be employed withchloroform, dimethylformamide, dimethylsulfoxide, dimethylacetamide,acetone and methylethyl ketone being exemplary. The solution is thenpoured over a clean glass plate and spread evenly to a uniform thicknesswith the aid of a doctor blade. The membranes are then air dried,removed from the glass plate and further dried in air under ambientconditions for a suitable period of time, generally in excess of 24hours. In other embodiments, these membranes can be manufactured by thevarious laboratory and commercial techniques known in the art. Thesemembranes can also be manufactured in structures other than films, suchas hollow fibers.

The membranes of this invention can be cast at any desirable thicknessalthough membranes having a thickness between 25 mils (1 mil equals 25micrometers) and 1,000 angstroms, preferably between 10 mils and 1,000angstroms. These membranes demonstrate good permeability, durability,flexibility, strength and corrosion resistance.

The process of this invention directed toward gas separations issuitable for separating any one of a number of different gases such ashydrogen, helium, nitrogen, oxygen, carbon monoxide, carbon dioxide,hydrogen sulfide, ammonia, water (vapor) and C₁ to C₄ hydrocarbons frommixtures containing the same. Typical gas mixtures where separation isdesirable include H₂ /N₂ ; H₂ /CO; H.sub. 2/C₁ to C₄ ; H₂ /0₂ ;H₂ /NH₃ ;CO₂ /C₁ to C₄ ; CO₂ /N₂ ; H₂ S/C₁ to C₄ ; 0₂ /N₂ ; N₂ /NH₃ ; He/C₁ to C₄; H₂ S/C₁ to C₄ and H₂ O/C₁ to C₄. The membrane can also be employed forthe separation of mixtures comprising three gases or more. It is to beunderstood that not all gas pairs or mixtures will be separatedoptimally over a given membrane of the present invention. So long as themembrane exhibits a selectivity for at least one gas in a mixture, ithas utility for that particular mixture. The semipermeable membranes ofthis invention find particular utility for the separation of gaseouscarbon dioxide-methane mixtures into their constituent parts, i.e.,enriched fractions of carbon dioxide and methane.

These membranes are also useful for separating liquid mixtures, such asethanol-water, water-aldehyde, salt water, carboxylic acid-water and thelike. If used to separate liquid mixtures into their constituent parts,then these membranes are used in the same manner as known membranes forthese separations. Furthermore, these membranes can be used in any oneof a number of different manners including reverse osmosis andpervaporation, the latter being a combination of permeation andevaporation.

The following examples are illustrative of specific embodiments of thisinvention and unless indicated to the contrary, all parts andpercentages are by weight.

SPECIFIC EMBODIMENTS

Polymer Preparation:

The polymers employed herein to manufacture the membranes were all basedupon polyphenylene oxide having a weight average molecular weight ofabout 46,000. Modification of the polymer by Friedel-Crafts according tothe process of the present invention commenced with the introduction of200 ml of a 5 percent solution of PPO in nitrobenzene and 10.926 g ofAlCl₃ into a 500 ml three necked flask equipped with a mechanicalstirrer, condenser and dropping funnel. 15.63 g of p-toluenesulfonylchloride dissolved in 56 ml nitrobenzene was then added over 30 minutesat 10° C. Following the addition, the dropping funnel was removed and adip tube was employed to purge the reaction mixture with dry N₂ in orderto drive off HCl generated. The flask was heated over a water bath to80° C. and maintained there for 270 minutes. At the end of this time,the reaction mixture was then washed with water until the pH was neutralfollowing which the separated polymer solution was dried on MgSO₄,filtered and precipitated in methanol.

The membrane tested herein as Example No. 1 was prepared from thearylsulfonated polyphenylene oxide polymers prepared by the foregoingdescription. The membrane itself was prepared by mixing a dilute (about5 to about 20 weight percent) solution of polymer prepared above in asuitable solvent, typically about 7 weight percent poured over a cleanglass plate and spread evenly to a uniform thickness with the aid of adoctor blade, air dried, removed from the glass plate, and further driedin air at ambient conditions for at least 24 hours. For purposes ofcomparison an unmodified PPO membrane film was also cast as Example No.2, a control.

Apparatus and Procedure:

A modified Gilbert cell was used to test the permeation of the twopolymer films. The test side was exposed to a carbondioxide/methane/nitrogen mixture in a mole ratio of 2.99:32:65. Thepermeant was picked up by a carrier gas, helium, and injectedintermittently through a sample valve into a GC column for analysis. Theexperiments were conducted at 23° C., the partial pressure of the testgas on the feed side was 29.7 psi (0.21 MPa) and the partial pressure ofthe product gas on the permeant side was about 0 and purged with 29.77psi (0.21 MPa) helium at a flow rate much in excess of the permeationrate. The area of the test membrane was 45.8 square cm. The filmthickness was about 1-2 mils. The carbon dioxide permeability and carbondioxide/methane selectivity figures are reported in Table I.

                  TABLE I                                                         ______________________________________                                        Separation Characteristics of Semipermeable Membranes                         Ex.                     Selectivity                                           No.     Membrane        CO.sub.2 /CH.sub.4                                                                      .sup.--PCO.sub.2                            ______________________________________                                        1       Arylsulfonylated PPO                                                                          23        75                                          .sup. 2.sup.a                                                                         PPO             20        64                                          ______________________________________                                         .sup.a Control                                                           

Selectivity, as is known, is a comparison of the permeability, P, of onegas divided by the permeability of the second gas in the mixture.Normally, the less permeable member of the gas pair is placed in thedenominator and the selectivity factor will be a number greater thanone. Permeability, in turn, is customarily calculated according to therelationship ##EQU1## where cc is the volume of the permeating gas atstandard temperature and pressure, cm is the thickness of the membrane,sec is the time in seconds for a given amount of gas to be permeated,cm² is the area of the membrane and cmHg is the pressure differentialover the membrane in cm of mercury. Permeability as such is reported inBarrers, one Barrer being equal to 1×10⁻¹⁰ P. Gas pressures on themembranes of this invention can range from about 0.10 to 200 MPa withfive to 100 MPa being preferred.

The above data clearly demonstrates the general superiority of membranesformed from aryl sulfonylated polypropylene oxide polymers over polyarylethers (PPO). Membranes formed from these modified polyphenylene oxidepolymers have also been shown to be essentially impervious to boilingwater while membranes formed from sulfonated polyphenylene oxide aregenerally water swellable.

As stated herein, R₂ in the sulfonyl group G can also be non-aromatic,i.e., C₁ to C₂₀ linear or branched hydrocarbon. By way of example, forExample No. 3 where R₂ in the sulfonyl group G is hexadecyl a differentprocedure was followed which commenced by contacting polyphenylene oxidein nitrobenzene (5 percent solution) in the presence of AlCl₃. To thismixture was added 1-hexadecanesulfonyl chloride while nitrogen gas wasbubbled therethrough. After a reaction time of six hours at 40° C., themixture was washed with water, dried on anhydrous MgSO₄, filtered andprecipitated from methanol.

A membrane was then prepared as described hereinabove and employed forthe separation of the CO₂ /CH₄ /N₂ mixture (2.99:32:65). For comparison,a membrane was also again prepared from an unmodified polyphenyleneoxide, Selectivity CO₂ /CH₄ for the hexadecyl sulfonylated polyphenyleneoxide membrane was equivalent to the unmodified polymer membrane whilePCO₂ was approximately 20 percent higher, thereby demonstrating theimprovement when the membrane comprised a sulfonylated polymer.

G can also be a sulfonamide and can be introduced according to theprocedure set forth for Example No. 1. Thus, in order to prepare ExampleNo. 4, 20 g of polyphenylene oxide in nitrobenzene (5 percent solution)was contacted with AlCl₃. To this mixture was added 12 g ofdimethylsulfamoyl chloride while nitrogen gas was bubbled therethrough.After a reaction time of six hours at 80° C., the mixture was washedwith water, dried on anhydrous MgSO₄, filtered and precipitated frommethanol.

A membrane was then prepared as described previously and employed forthe separation of the CO₂ /CH₄ /N₂ mixtures (2.99:32:65). Permeabilitieswere determined as follows: PCH₄ =3.31; PCO₂ =80.99; PN₂ =2.45.Selectivities were also determined as follows: PCO₂ /PCH₄ =24.47; PCO₂/PN₂ =33.06. The polymer film was found to possess good strength andsome elasticity. Comparisons with the unmodified PPO, Example No. 2,revealed a 27 percent increase for PCO₂ and a 22 percent increase forPCO₂ /PCH₄ selectivity.

As was also stated hereinabove, the number of pendant groups Gintroduced onto the polyarylene units can be at least one group G per 20polyarylene units and is preferably one group G per four arylene unitsto two groups G per arylene unit. Stated alternatively, the groups G canbe present in an amount of from about five percent (0.05 mole) to about200 percent (2.0 mole), based upon the number of polyarylene units.

In order to demonstrate that the number of pendant groups, introducedaccording to the process of the subject invention, could vary between 25to 200 percent, reference should be made to Table II which providesreactant and catalyst ratios for two catalysts, with reactionconditions. Polyphenylene oxide PPO was again modified withtoluenesulfonyl chloride, RSO₂ Cl. It will be observed that bothcatalysts AlCl₃ and FeCl₃ were readily employed.

                                      TABLE II                                    __________________________________________________________________________    Control Over the Number of Sulfonyl Groups                                    Added Per PPO Backbone Unit                                                   PPO/RSO.sub.2 Cl                                                                          RSO.sub.2 CL/AlCl.sub.3                                                               RSO.sub.2 Cl/FeCl.sub.3                                                               Temp °C.                                                                      Time                                       Ex. No.                                                                            (mole/mole)                                                                          (mole/mole)                                                                           (g/g)   (min.                                                                            max.)                                                                             (min.)                                     __________________________________________________________________________     5   1/0.25  1/0.275                                                                              --      15 80  360                                         6   1/0.25 --      100/1   15 80  360                                         7   1/0.50  1/0.55 --      15 80  360                                         8   1/0.50 --      100/1   15 80  360                                         9   1/1    1/1.1   --      15 80  360                                        10   1/1    --      100/1   15 80  360                                        11   1/1.5  1.165   --      15 80  390                                        12   1/1.5  --      100/2   15 80  390                                        13   1/2    1/2.2   --      15 90  480                                        14   1/2    --      100/4   15 90  480                                        __________________________________________________________________________

The compositions of Examples No. 5-14 were determined via elementalanalysis and NMR and were found to be one sulfonyl per four aryleneunits, Examples No. 5 and 6; one sulfonyl per two arylene units,Examples No. 7 and 8; one sulfonyl per single arylene unit, Examples No.9 and 10; three sulfonyls per two arylene units, Examples No. 11 and 12,and two sulfonyls per single arylene unit, Examples No. 13 and 14.

Thus, it has been demonstrated herein that the process of the presentinvention is useful for the synthesis of sulfonyl pendant groups ontopolyaryl ethers via Friedel-Crafts reactions. The novel polymersresulting therefrom have good solubilities, enhancing the possibility ofcasting films as polymer membranes from a large number of solvents manyof which would not be useful for the dissolution of unmodified PPO. Theimproved solubilities, in turn, increase the range of casting solutionconcentrations which can improve the yield of performance compositemembranes in the manufacturing process.

For example, PPO is commonly dissolved in chloroform and, in the processof forming hollow fibers of the membrane, the filament is coagulated inmethanol, a nonsolvent for PPO. By employing a modified PPO according tothe present invention, polar organic solvents can be selected, such asdimethyl formamide (DMF), dimethylsulfoxide (DMSO), dimethylacetamide,N-methyl pyrolidone and the like, and the spun filament can becoagulated in water. The advantages include better control over poresize because the polymer solvents are less volatile than chloroform. Inthe formation of films, for instance, very rapid evaporation ratesproduce surface cooling leading to localized precipitation andnonuniform, stressed film. Also, as a coagulant, water is cheaper andsafer than methanol.

It is to be understood that the novel polymers and permselectivemembranes prepared therefrom can comprise other components than thesulfonylated PPO exemplified herein, the examples having been providedmerely to demonstrate practice of the subject invention. Those skilledin the art may readily select other polyarylenes and pendant groups,e.g., alkyls, acyls and phosphonyls according to the disclosure madehereinabove.

Lastly, although operability of the process to separate CO₂ from CH₄ andN₂ has been demonstrated herein, the membranes of the present inventionand process for separating gases therewith can be employed with othergas mixtures so long as the members of a given pair have differentpermeability rates from each other.

Thus, it is believed that any of the variables disclosed herein canreadily be determined and controlled without departing from the spiritof the invention herein disclosed and described. Moreover, the scope ofthe invention shall include all modifications and variations that fallwithin the scope of the attached claims.

We claim:
 1. Novel substituted polyarylene polymers having the formula##STR21## wherein each R is independently a C₁ to C₈ aliphatic or a C₅to C₇ cycloaliphatic radical, an aryl radical having the formula##STR22## wherein each R₁ is independently a C₁ to C₈ aliphatic radicaland p is an integer of 0 to 4, each radical being free of a tertiaryalpha-carbon atom; A is hydrogen, halogen, an aliphatic or an arylradical; Y is a divalent oxygen or sulfur atom or a carbonate group; nis an integer of from about 75 to about 10,000; andwherein G is presentin at least five percent of said polyarylene units and is selected fromthe group consisting of alkyl sulfonyls having the formula ##STR23##where R_(2a) is a C₁ to C₂₀ aliphatic radical and sulfonamides havingthe formula ##STR24## where R₂ is a C₁ to C₂₀ aliphatic or aryl radicalof the formula ##STR25## or a naphthyl radical where R₁ and p are asdescribed above.
 2. Novel substituted polyarylene polymers having theformula ##STR26## wherein each R is independently a C₁ to C₈ aliphaticor a C₅ to C₇ cycloaliphatic radical, an aryl radical having the formula##STR27## wherein each R₁ is independently a C₁ to C₈ aliphatic radicaland p is an integer of 0 to 4, each radical being free of tertiaryalpha-carbon atom; A is hydrogen, halogen, an aliphatic or an arylradical; Y is a divalent oxygen or sulfur atom or a carbonate group; nis an integer of from about 75 to about 10,000; andwherein G is presentin at least five percent of said polyarylene units and is selected fromthe group consisting of phosphorus groups having the formula

    P (R.sub.5).sub.3 q

where R₅ is selected from the group consisting of R₄ and O--R₄ andmixtures thereof where R₄ is a C₁ to C₂₀ aliphatic or an aryl radical ofthe formula ##STR28## where R₁ and p are as defined in claim 1 and q isan integer of from 1 to 3.